title: Method development and validation for cyprodinil and fludioxonil in blueberries by solid-phase microextraction gas chromatography, and their degradation kinetics.
abstract: A method of analysis for residues of cyprodinil and fludioxonil in blueberries was developed. Fungicide residues were determined by solid-phase microextraction coupled to GC with nitrogen-phosphorous detection. The effect of pH values and fibre coatings was studied. The solid-phase microextraction fibre coating selected was 100 µm polydimethylsiloxane. The method was selective, with adequate precision and high accuracy and sensitivity. Apparent recoveries ranged within the 99-101% range for cyprodinil and the 98-100% range for fludioxonil; LODs and LOQs were 1.2 and 3.9 µg/kg for cyprodinil and 0.4 and 1.3 µg/kg for fludioxonil, respectively. Statistical parameters indicated a matrix effect; consequently, calibration was performed on spiked samples. Degradation of cyprodinil and fludioxonil was studied in a blueberry field located in Concordia (Argentina), with fruit from Emerald and Jewel varieties. The degradation of these fungicides in both blueberry varieties studied followed first-order rate kinetics for both fungicides, and the half-life for cyprodinil was 2.2 and 3.4 days for Emerald and Jewel cultivars, respectively, and for fludioxonil was 12.7 and 16.3 days, respectively.
authors.affiliation: Facultad de Ciencias de la Alimentación, Universidad Nacional de Entre Ríos, Concordia, Argentina. munitzm@fcal.uner.edu.ar
authors.forename: Martín S
authors.initials: MS
authors.lastname: Munitz
authors.forename: Silvia L
authors.initials: SL
authors.lastname: Resnik
authors.forename: María I T
authors.initials: MI
authors.lastname: Montti
mesh_terms: D029798:Blueberry Plants / Q000737:chemistry*; D002849:Chromatography, Gas / Q000379:methods*; D004149:Dioxoles / Q000032:analysis*; D005659:Fungicides, Industrial / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D011743:Pyrimidines / Q000032:analysis*; D011758:Pyrroles / Q000032:analysis*; D052617:Solid Phase Microextraction
chemical_list: D004149:Dioxoles; D005659:Fungicides, Industrial; D011743:Pyrimidines; D011758:Pyrroles; C108338:cyprodinil; C108339:fludioxonil